Data storage systems can fall into a plurality of categories, such as Network Attached Storage (NAS) and Storage Area Networks (SAN). A NAS system can be a stand-alone, network-accessible, storage device that can provide file-level access to electronic data. A SAN array can be a dedicated storage system that can connect numerous storage resources to one or many hosts. A SAN can provide block-level access to electronic data through one or more protocols, e.g., (SCSI-based protocols such as Fiber Channel or iSCSI), which can be used by a connected host to provide a file system.
Storage systems can be employed that include two storage processors and one or more storage devices. Examples of such storage devices include disk storage arrays and network storage arrays. From the perspective of a host that issues input/output (IO) requests to the storage processors to read, write, copy, and/or allocate data storage on the storage devices, the storage devices appear accessible from either storage processor. Using two active storage processors to perform IO requests can improve the overall performance of the storage system.